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certain - definition and synonyms

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adjective     certain pronunciation in British English
  1. 1
    [never before noun] having no doubts that something is true

    I’m not absolutely certain, but I think I’m right.

    certain (that):

    You can be pretty certain she’s not going to like it.

    certain who:

    We still can’t be certain who is going to win.

    certain of/about:

    I’ve never been more certain of anything in my entire life.

    You don’t seem too certain about it.

    know/say for certain:

    I think I met her in 1985, but I can’t say for certain.

  2. 2
    definitely going to happen

    They face certain death if they are sent back to their home country.

    Success is by no means certain.

    be certain to do something:

    Interest rates seem certain to rise next month.

    it is certain (that):

    It’s not certain that this method would have worked.

    certain of:

    Mexico is now certain of a place in the finals.

    1. a.
      definitely true

      One thing was certain: someone had been in his room.

    2. b.
      definitely known
      it is certain who:

      It’s not yet certain who the driver of the car was.



to manipulate someone psychologically so that they begin to question their own perceptions and memories

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Open Dictionary

Dunning-Kruger effect

the phenomenon by which an incompetent person is too incompetent to understand his own incompetence

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